Things might work perfectly or not at all. Fortunately, with logging
enabled, troubleshooting is easy, because Heartbeat outputs informative log
messages. Heartbeat even will let you know when a previous log message
is not something you have to worry about. When bringing a new cluster
on-line, I usually open an SSH terminal to each cluster member and
tail the messages file like so:

tail -f /var/log/messages

Then, in separate terminals, I start up Heartbeat. If there are any
problems, it is usually pretty easy to spot them.

Heartbeat also comes with very good documentation. Whenever I run
into problems, this documentation has been invaluable. On my system, it
is located under the /usr/share/doc/ directory.

Conclusion

I've barely scratched the surface of Heartbeat's capabilities
here. Fortunately, a lot of resources exist to help you
learn about Heartbeat's more-advanced features. These include active/passive and active/active clusters with N number of nodes,
DRBD, the Cluster Resource Manager and more. Now that your feet are
wet, hopefully you won't be quite as intimidated as I was when I first
started learning about Heartbeat. Be careful though, or you might end
up like me and want to cluster everything.

Daniel Bartholomew has been using computers since the early 1980s when his
parents purchased an Apple IIe. After stints on Mac and Windows machines,
he discovered Linux in 1996 and has been using various distributions
ever since. He lives with his wife and children in North Carolina.

Trending Topics

Webinar: 8 Signs You’re Beyond Cron

Scheduling Crontabs With an Enterprise Scheduler
11am CDT, April 29th

Join Linux Journal and Pat Cameron, Director of Automation Technology at HelpSystems, as they discuss the eight primary advantages of moving beyond cron job scheduling. In this webinar, you’ll learn about integrating cron with an enterprise scheduler.